Copper supplementation

In supplementation, it is preferable to use copper citrate, as it is the most bioavailable salt, rather than copper oxide.

Foods with copper

Foods with trace elements

The foods that contain the most trace elements (zinc, selenium, chromium, copper, manganese, and molybdenum):

• Nuts (all types).
• Wholegrain cereals.

Foods with copper: Beef liver, shellfish, nuts, cashews, seeds (like sesame and sunflower), chocolate, avocados, chick peas, and whole grains.

Foods with zinc. The highest concentrations of zinc are found in red meats, particularly beef and lamb, and in the livers of these animals.

Intake and deficiencies

Copper forms a part of important antioxidant and detoxifying enzymes like the SODs (Miao and St Clair 2009; Johnson and Giulivi 2005), and it participates in anti-inflammatory and tissue-restoration action (Pickart 2008).

Intake and deficiencies

Deficient copper intake is common in the population.

Intake. The concentration of copper depends on external inputs. According to different surveys, just 25% of the U.S. population consumes the recommended intake (PRI) of copper. Typical U.S. diets provide approximately half of this amount, and some diets in the main industrialized countries provide even lower amounts (less than 40% of the PRI). In the Great Britain, for example, the daily recommended intake is around 0.4 mg/day in the first years of life and up to 1.2 mg/day in adulthood. Additionally, the latest studies raise serious doubts in relation to diets containing less than 1 mg/day for adults (Anonymous, 2010).

Anemia is a sign of copper deficiency.

Nutrients. Excessive zinc supplementation can cause a copper deficiency. It is thought that zinc and copper compete for absorption in the digestive tract, and therefore a diet with too much of either of these minerals can lead to a deficiency in the other. High intake of ascorbic acid and zinc can protect against copper toxicity by preventing intestinal absorption Gaetke LM, Chow CK 2003).

Milk and egg proteins can interfere with copper absorption.

Drugs. Antacids can accentuate a marginal copper deficiency.

Bibliography

• Anonymous (1980). Copper. Recommended Dietary Allowances. Washington, D.C., National Research Council, Food Nutrition Board, NRC/NAS: 151-154
• (1994).
  “Pesticide Information Profile for Copper Sulfate.”
  EXTOXNET Extension Toxicology Network Retrieved 26 Jan, 2010, fromhttp://pmep.cce.cornell.edu/profiles/extoxnet/carbaryl-dicrotophos/copper-sulfate-ext.html.
• (2010).
  “Copper in Human Health.”
  Copper Org.
  The ultimate source for information on copper and copper alloys Retrieved 26 Jan, 2010.
• Johnson, F. and C. Giulivi (2005). “Superoxide dismutases and their impact upon human health.” Mol Aspects Med 26(4-5): 340-352.
• Johnson, L. E. (2005). “Copper.” The Merck Manuals. Online Medical Library. The Merck Manuals for Healthcare Professionals. Retrieved 26 Jan, 2010, fromhttp://www.merck.com/mmpe/sec01/ch005/ch005c.html?qt=copper%20and%20milkalt=sh.
• Miao, L. and D. K. St Clair (2009). “Regulation of superoxide dismutase genes: implications in disease.” Free Radic Biol Med 47(4): 344-356.
• Pickart, L. (2008). “The human tri-peptide GHK and tissue remodeling.” J Biomater Sci Polym Ed 19(8): 969-988.
• Saari, J. T. (2000). “Copper deficiency and cardiovascular disease: role of peroxidation, glycation, and nitration.” Can J Physiol Pharmacol 78(10): 848-855.
• Vonk, W. I. and L. W. Klomp (2008). “Role of transition metals in the pathogenesis of amyotrophic lateral sclerosis.” Biochem Soc Trans 36(Pt 6): 1322-1328.
• Waggoner DJ, Bartnikas TB (1999). “The role of cooper in neurodegenerative disease”. Neurobiol Dis.1999 Aug;6(4):221-30.
• Wintergerst, E. S., S. Maggini, et al. (2007). “Contribution of selected vitamins and trace elements to immune function.” Ann Nutr Metab 51(4): 301-323.

Reference values

NRV, PRI, UL for copper

The NRV is 1 mg. The PRI is 0.9–1.0 mg/day

The UL is 5 mg.

Copper can be toxic at high doses.

Copper toxicity comes from eating acidic foods cooked using copper pots or utensils. Thus, the cases of childhood liver cirrhosis have been associated with boiling milk in copper pots. The Merck Manual postulates that there is a genetic problem linked to this type of cirrhosis (Johnson 2005). Given that copper is actively excreted by the human body, chronic copper toxicosis in humans in the absence of genetic defects in the handling of copper have not been demonstrated (Anonymous 2010).

NRV: Nutrient Reference Value. These are the daily amounts recommended for vitamins and minerals (micronutrients only) considered sufficient in the European Union to prevent a deficit in most healthy individuals in the population. They are the values used for labeling and claims.

PRI: Population Reference Intake. These are the reference values for a specific population group, defined as the amount of energy and/or nutrients (macronutrients and micronutrients) recommended to cover the nutritional needs of practically the entire population. They refer to healthy population groups. The values are expressed per person per day, as a 15-day average. To account for individual differences in digestive and metabolic processes, the PRI figure used for each nutrient is the average plus twice the standard deviation (except for energy, for which the average is used), thereby including almost all healthy individuals in the group (97.5%).

UL: Tolerable Upper Intake Level: the maximum level of total daily intake of a nutrient in a context of long-term or chronic consumption which does not pose a risk to health.